iBasso DC02 has AKM4490EQ DAC on board and unbalanced 3.5 out only. Which is good specs, especially for this size! (But I dont know which Amps there installed is) Cayin N5IISS have ESS 9018K2M DAC and has four Amps (2 for balanced out, 1 for unbalanced and 1 for line-out). I pretty sure that Cayin`s Amps (OPA1622) defenetly better than in DC02 (and of cource more powerfull). And scheme and another components are higher level (as Capacitors and blah). Cayin`s sound more neutral, detailed, may be not wider but deeper, more immersive 3D soundstage. Also has more detailed and deeper bass (also has accent on bass as DC02), natural vocals and crisp high frecs! I think it`s another level of sound, no matter which DAC there are installed. But the DAP has many problems, lazy UI and buggy controlls. Thats annoying me all the time I use it, especially in Car. :| Thats why I bought DC02, to use it in Car, mostly. Also it`s dont need any charging, has very high level sound and small convinient size!